Check out example codes for "'The route template separator character '/' cannot appear consecutively. It must be separated by either a parameter or a literal value. Parameter name: routeTemplate'". It will help you in understanding the concepts better.

Code Example 1

In my case, I had an extra '/' on my Route query string.

LIKE:

[Route("get/liked//{id}")]
[HttpGet("[action]")]
public async dynamic GetLikedPost(int id)

INSTEAD OF:

[Route("get/liked/{id}")]
[HttpGet("[action]")]
public async dynamic GetLikedPost(int id)

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